Back cover of a watch with a variable pattern



FIG. 1 is a top surface of my new and ornamental design for a back coverof a watch having a variable pattern in which the bars extend radiallyfrom a central portion. When the watch is moved, the underlyingmechanism causes the design formed by the bars to vary irregularly innumber, width, and spacing. The watch case does not form part of theclaimed design. The design is comprised solely of the back cover. Theparticular watch case is shown only as environment.

FIG. 2 is a top surface view showing a second variable pattern; and,

FIG. 3 is a top surface view showing a third variable pattern.

The ornamental design for a back cover of a watch with a variablepattern, as shown and described.